Photovoltaic panels produce DC (direct current) voltage. In order to feed power to a home or city electrical grid, the voltage needs to be converted to AC (alternating current). Solar arrays typically have a large central inverter that converts the system voltage from DC to AC. Power flows from the solar modules to the inverters and then to the electrical grid.
Often these large central inverters are placed in garages, sheds, hidden behind paneling, etc. to keep them protected and out of sight. Larger central inverters, however, are sometimes too large or too heavy to hide for some solar projects.
Microinverters are small inverters used to convert the output from a small number of modules from DC to AC. Depending on the capacity of the microinverter, there may be as many as one inverter for each panel. The microinverters are physically smaller and lighter than larger central inverters although more of them are needed to take the place of the larger central inverters.
Solar panels may also be connected to power optimizers, which are used to maximize the energy developed from the solar modules. Such optimizers are known in the art and can individually tune the performance of a photovoltaic panel to match the performance of an inverter. Microinverters can combine a power optimizer and small inverter in a single housing that is used for every panel. Alternatively, a power optimizer may be located separate from the inverter in a separate housing.